package one.one.twenty;

public class LnN {

	static long fac(int n) {
		if (n == 0 || n == 1)
			return 1;
		return n * fac(n - 1);
	}

	static long lnn(int n) {
		return (long)Math.log(fac(n));
	}

	public static void main(String[] args) {
		System.out.println(lnn(10));

	}

}
